NASA says solar activity is increasing

A new NASA study shows Sun has become increasingly active

The sun has become more and more active over the last 16 years, in a turn that surprised scientists and could affect space weather and technology on Earth, NASA announced. The Sun has become increasingly active since 2008, a new study shows. A new research, conducted by two NASA scientists and published earlier, shows that solar activity has ramped up after 2008, an unexpected reversal following a decades-long decline that was initially thought to foreshadow a period of historic inaction on the surface of the sun. According to the official website of the organization, solar activity is known to fluctuate in cycles of 11 years, but there are longer-term variations which can last decades. It looked like the Sun was heading toward a historic lull in activity. This trend flipped in 2008, according to new research. Since the 1980s, the amount of solar activity had been steadily decreasing all the way up to 2008, when solar activity was the weakest on record. At that point, scientists expected the Sun to be entering a period of historically low activity.  But then the Sun reversed course and started to become increasingly active, as documented in the new study. It’s a trend that researchers said could lead to an uptick in space weather events, such as solar storms, flares and coronal mass ejections.

An uptick in solar activity could influence space weather, potentially leading to more solar storms, solar flares and coronal mass ejections, the researchers found. Space weather patterns have the potential to directly impact spacecraft operations and the safety of astronauts, but they may be felt on Earth, too, as space weather can affect power grids, GPS systems and radio communication, according to NASA. “All signs were pointing to the Sun going into a prolonged phase of low activity,” said Jamie Jasinski of NASA’s Jet Propulsion Laboratory in Southern California, lead author of the new study. “So it was a surprise to see that trend reversed. The Sun is slowly waking up.” The downward trend was documented from the 1980s until 2008, when the space agency determined that the sun had reached its weakest point on record. The sun's action, or inaction, tends to fluctuate in 11-year cycles, according to NASA, although some patterns draw on longer.

The earliest recorded tracking of solar activity began in the early 1600s, when astronomers, including Galileo, counted sunspots and documented their changes. Sunspots are cooler, darker regions on the Sun’s surface which are produced by a concentration of magnetic field lines. Areas with sunspots are often associated with higher solar activity, such as solar flares, which are intense bursts of radiation, and coronal mass ejections, which are huge bubbles of plasma that erupt from the Sun’s surface and streak across the solar system. Earth is currently in Solar Cycle 25, which began in 2020. The last cycle maintained an average length of 11 years and was the weakest solar cycle to occur in a century, according to the National Weather Service. Scientists thought the sun would stay in what they dubbed "deep solar minimum," believing that the stretch of quietness from the sun would continue, eventually leading to a new phase of record low activity. "But then the trend of declining solar wind ended," Jasinski said. NASA scientists track these space weather events because they can affect spacecraft, astronauts’ safety, radio communications, GPS, and even power grids on Earth. Space weather predictions are critical for supporting the spacecraft and astronauts of NASA’s Artemis campaign, as understanding the space environment is a vital part of mitigating astronaut exposure to space radiation.

Jasinski study, co-authored by Marco Velli, a fellow researcher at the Jet Propulsion Laboratory, tracked increasing bursts of solar plasma and stronger magnetic field measurements throughout the solar system, which are all affected by the sun. NASA’s IMAP (Interstellar Mapping and Acceleration Probe) and Carruthers Geocorona Observatory missions, as well as the National Oceanic and Atmospheric Administration’s SWFO-L1 (Space Weather Follow On-Lagrange 1) mission, will provide new space weather research and observations which will help to drive future efforts at the Moon, Mars and beyond. Solar Cycle 26 is expected to begin some time between January 2029 and December 2032, the National Oceanic and Atmospheric Administration said, but the agency has not yet produced a prediction for the next cycle. In order to better track space weather, NASA announced that it will launch the Interstellar Mapping and Acceleration Probe (IMAP) and Carruthers Geocorona Observatory missions, as well as the NOAA's SWFO-L1 mission, from Falcon 9 soon. It comes just a few months after SpaceX helped NASA launch TRACERS twin satellites which are studying how the electrically-charged solar wind interacts with Earth's magnetic field.

Solar activity affects the magnetic fields of planets throughout the solar system. As the solar wind, a stream of charged particles flowing from the Sun, and other solar activity increase, the Sun’s influence expands and compresses magnetospheres, which serve as protective bubbles of planets with magnetic cores and magnetic fields, including Earth. These protective bubbles are important for shielding planets from the jets of plasma which stream out from the Sun in the solar wind. "Space weather predictions are critical for supporting the spacecraft and astronauts of NASA's Artemis campaign, as understanding the space environment is a vital part of mitigating astronaut exposure to space radiation," NASA said. Over the centuries that people have been studying solar activity, the quietest times were a seven-decade stretch from 1645 to 1715 and a four-decade stretch from 1790 to 1830. “We don’t really know why the Sun went through a 40-year minimum starting in 1790,” Jasinski said. “The longer-term trends are a lot less predictable and are something we don’t completely understand yet.” In May 2024, NASA officials recorded the strongest geomagnetic storm in more than 20 years. Several X-class solar flares, the largest of B-class, followed by C and M, sent the northern lights to far lower latitudes than normal, as far south as Mexico. “But then the trend of declining solar wind ended, and since then plasma and magnetic field parameters have steadily been increasing,” said Jasinski, who led the analysis of heliospheric data publicly available in a platform called OMNIWeb Plus, run by NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

In the two-and-a-half decades leading up to 2008, sunspots and the solar wind decreased so much that researchers expected the “deep solar minimum” of 2008 to mark the start of a new historic low-activity time in the Sun’s recent history. Geomagnetic storms have the ability to impact how and whether technology functions on a massive scale, electrical engineer David Wallace explained. "Internet service providers could go down, which in turn would take out the ability of different systems to communicate with each other. High-frequency communication systems such as ground-to-air, shortwave and ship-to-shore radio would be disrupted," Wallace wrote. The data Jasinski and colleagues mined for the study came from a broad collection of NASA missions. Two primary sources, ACE (Advanced Composition Explorer) and the Wind mission, launched in the 1990s and have been providing data on solar activity like plasma and energetic particles flowing from the Sun toward Earth. The spacecraft belong to a fleet of NASA Heliophysics Division missions designed to study the Sun’s influence on space, Earth and other planets in the universe.